Propellers are typically used as power thruster for aerial vehicles or ships. A propeller may include a base body and blades mounted onto the base body. A driving shaft can be connected with the base body. The driving shaft can be driven to rotate by an electric motor, and can thus bring the blade to rotate together. The driving shaft can be connected with the base body through a threaded fitting. Alternatively, screw holes can be provided on the base body and the driving shaft, and then the base body can be fixedly mounted on the driving shaft with screws.
In case the base body is connected with the rotating shaft through a threaded fitting, a tightening direction of the base body is the same as a rotating direction of the blades during an operation of the propeller, such that the blades can be firmly connected with the rotating shaft during a startup and an operation of the propeller. However, if the blades experience a sudden deceleration or a large change in acceleration, the threaded fitting between the base body and the driving shaft may be easily loosen or released. In addition, in case of vibrations having large amplitude, the fitting between the base body and the driving shaft may be loosened, resulting in the blade emitting out from the propeller. On the other hand, the screw connection between the base body and the driving shaft may not be readily detachable.